Help me worldbuild!

Hi! So I have this problem building worlds.. I'm good at creating new characters and scenes, they just show up in my head and I write them down. But when I want to creat a new world to put all these characters and senes in, I can't figure out what it should be about.. I have for a long time trying do sci-fi worlds but the main problem are what are the problems the head character should solve?! I can't figure it out without sounding like already known books (Marie Lu, Suzanne Collings, Cassandra Clare etc).

Do you have any ideas of what I should do?

Maybe you should make them have to find something or the the world ends. idk just a thought. Hope It helped.

Thanks! But I can't figure out what they should find tho..

if it's sci-fi, maybe there's a huge government secret that the protags stumble upon (alien cover-up, cataclysmic event, asteroids, intergalactic war). maybe their perfect government isn't actually that perfect but everyone's been brainwashed into thinking so and don't believe a bunch of ragtag teenagers. maybe the population has been locked up in giant supercities with no access to the outside world for reasons and the protags decide to break the law and escape only to find the outside world isn't so forgiving. maybe the protags don't need to find something so much as other people need to find them. just some ideas to start :)

Wow! Thank you!